1. Field of the Invention
The present invention relates to a variable valve lift apparatus, and more particularly to a variable valve lift apparatus for varying the lift amount of a valve.
2. Description of Related Art
A general cam that is mounted on an engine cannot vary the lift amount of a valve and cannot optimize fuel consumption and power.
Recently, experiments that change the lift amount, the opening timing, and the opening period of intake/exhaust valves have been carried at a good pace in order to improve output and efficiency of an engine.
Among them, there is a continuously variable valve lift apparatus (CVVL).
The continuously variable valve lift apparatus varies the lift amount of the intake/exhaust valves in accordance with driving conditions of the engine.
Accordingly, intake flux can be maximized in high speed/load conditions of driving in which high power is demanded, and simultaneously the intake flux can be minimized in low speed/load conditions of driving in which it is necessary to reduce exhaust gas and fuel consumption.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.